Investigating the In-vivo Antiplasmodial Properties of Aqueous Extract of Moringa oleifera Lam (Moringaceae) Leaves
Emmanuel Orman *
Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana.
Phyllis Addo
Department of Animal Experimentation, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra, Ghana.
Michael Fokuo Ofori
Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra, Ghana.
Reimmel Kwame Adosraku
Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana.
*Author to whom correspondence should be addressed.
Abstract
Aim: The study investigated Moringa oleifera Lam (Moringaceae), for its in-vivo antiplasmodial properties, using a murine model involving Plasmodium berghei.
Study Design: Experimental.
Places of Study and Duration: Department of Pharmaceutical Chemistry, KNUST, Department of Immunology, NMIMR and Department of Animal Experimentation, NMIMR, May – November, 2013.
Methodology: Phytochemical investigation was conducted on powdered plant material and aqueous leaf extract (ML), to determine the presence of secondary metabolites using standard methods. Using 4-day suppressive and 7-day curative tests respectively, ML at 250-1000 mg/kg, was evaluated for in-vivo antiplasmodial activity in P. berghei infected male ICR mice (25-30 g), using Artemether-Lumefantrine (A/L) at 4 mg/kg as reference drug. The effect of ML on the body weights and the survival of the mice, as well as the effect on improvement in clinical signs was also monitored.
Results: ML extract was found to contain alkaloids, saponins, flavonoids and tannins. The extracts (250-1000 mg/kg) produced significant reduction in parasitemia in the four-day suppressive test (F6,49 = 4.309; p =.0014). However, 250 mg/kg (69.31%; p< .001) and 500 mg/kg (77.26%; p< .001) extracts exhibited relatively higher activities compared to 750 mg/kg (25.28%; p< .001) and 1000 mg/kg (07.12%; p> .05). In the curative test, similar results were obtained with significant parasitemia reduction for 250 mg/kg (AUC = 52.52±6.732; p< .01) and 500 mg/kg (AUC = 49.62 ± 3.804; p< .01) compared to the positive control group (AUC = 101.3±14.32). Piloerection, lethargy and decreased locomotion were observed to be progressive in all infected experimental groups except A/L. Survival data showed that, although 750 mg/kg and 1000 mg/kg groups recorded relatively higher mortalities, statistical analysis didn’t indicate significant difference.
Conclusion: ML extract demonstrated in-vivo antiplasmodial activity; probably due to the alkaloids, saponins, flavonoids and tannins in its composition.
Keywords: Moringa oleifera, antiplasmodial, phytochemicals, suppressive, piloerection, lethargy, survival and mortality.